Development of a Multifunctional Platform Based on Strong, Intrinsically Photoluminescent and Antimicrobial Silica‐Poly(citrates)‐Based Hybrid Biodegradable Elastomers for Bone Regeneration

Abstract

Biodegradable biomaterials with intrinsically multifunctional properties such as high strength, photoluminescent ability (bioimaging monitoring), and antimicrobial activity (anti‐infection), as well as high osteoblastic differentiation ability, play a critical role in successful bone tissue regeneration. However, fabricating a biomaterial containing all these functions is still a challenge. Here, urethane cross‐linked intrinsically multifunctional silica‐poly(citrate) (CMSPC)‐based hybrid elastomers are developed by first one‐step polymerization and further chemical crosslinked using isocyanate. CMSPC hybrid elastomers demonstrate a high modulus of 976 ± 15 MPa, which is superior compared with most conventional poly(citrate)‐based elastomers. Hybrid elastomers show strong and stable intrinsic photoluminescent ability (emission 400–600 nm) due to the incorporation of silica phase. All elastomers exhibit high inherent antibacterial properties against Staphylococcus aureus. In addition, CMSPC hybrid elastomers significantly enhance the proliferation and metabolic activity of osteoblasts (MC3T3‐E1). CMSPC hybrid elastomers significantly promote the osteogenic differentiation of MC3T3‐E1 by improving alkaline phosphatase activity and calcium biomineralization deposits, as well as expressions of osteoblastic genes. These hybrid elastomers also show a minimal inflammatory response indicated by subcutaneous transplantation in vivo. These optimized structure and multifunctional properties make this hybrid elastomer highly promising for bone tissue regeneration and antiinfection and bioimaging applications.

Hybrid polymer biomaterials for bone tissue regeneration

“…These hybrid elastomers still have the intrinsic problem of poor interface intensity between the inorganic phase and polymers. Therefore, our group introduced bioactive silica into PCD elastomers through a one-step thermal polymerization method [30,31,78,79]. The inorganic silica phase was bonded with the PCD polymer chain through covalent bonds.…”

“…The inorganic silica phase was bonded with the PCD polymer chain through covalent bonds. The resulting hybrid polycitrate-silicon (PCS) elastomers demonstrated significantly improved elastomeric behavior, mechanical strength and cellular biocompatibility (Figure 7) [30]. SBGS-based PGS hybrid elastomers were also fabricated successfully through the direct hybridization of SBGS and PGS solution [29].…”

“…Our group developed silicon-based polymer elastomers with controlled biodegradation for applications in bone regeneration [29–31]. The results demonstrated that poly(citrate-siloxane) (PCS) hybrid elastomers significantly enhanced attachment and proliferation of various cells, including cells derived from both hard and soft tissue [30,31]. PCS-based hybrid polymer could also significantly enhance osteoblastic differentiation, cellular biominerialization of MC3T3-E1 cells [78,79].…”

“…a,b) Fabrication of Multifunctional silica-poly(citrate) (MSPC) and crosslinked MSPC (CMSPC) elastomers by polycondensation of citric acid (CA), 1,8-octylene glycol (OD), aminosilane (AS), as well as the chemical crosslinking with hexamethylene diisocyanate (HDI) and c) schematic diagram showing the formation of CMSPC hybrid elastomers matrix. Reproduced from Ref [30]. …”

Photoluminescent arginine‐functionalized polycitrate with enhanced cell activity and hemocompatibility for live cell bioimaging

“…In recent years, poly (citrate) (PC)‐based polymers have been gaining great interest in biomedical application such as tissue regeneration and gene delivery, due to their high biocompatibility, controlled biodegradation, and low cost . In previous study, our group developed a series of highly elastomeric PC‐based hybrid polymers, demonstrated their potential biomedical applications including bone tissue repair and gene delivery in vitro and in vivo . However, the conventional PC polymer shows the poor hydrophilicity and photoluminescent property, which limit their promising application in live cell imaging.…”